GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Turn the ignition OFF.
  2. Roll down the windows.
  3. Close all of the doors.
  4. Connect a scan tool.
  5. Turn the ignition to the ON position.
  6. Using the scan tool, inspect for any DTCs in the body control module (BCM).

Does the scan tool show any DTCs?

--

Go to Diagnostic System Check - Body Control System in Body Controls

Go to Step 2

2

Remove and inspect the LOCK and the UNLOCK fuses.

Is 1 or both fuses open?

--

Go to Step 3

Go to Step 4

3

  1. Locate and repair the CKT 255 (GRY/BLK) or CKT 254 (TAN/BLK) wire for a short to ground.
  2. Replace the fuse(s).

Is the repair complete?

--

System OK

--

4

  1. Re-install the fuses.
  2. Disconnect the inoperative actuator.
  3. Connect a test lamp from terminal A to ground of the harness side.
  4. Depress the switch to the unlock position.

Does the test lamp light?

--

Go to Step 5

Go to Step 6

5

  1. Connect a test lamp from terminal B to ground of the harness side.
  2. Depress the switch to the lock position.

Does the test lamp light?

--

Go to Step 8

Go to Step 9

6

Is this vehicle equipped with 1 lock relay and 2 unlock relays?

--

Go to Step 10

Go to Step 7

7

  1. Locate and repair the open in CKT 694 (TAN) or CKT 254 (TAN/BLK) wire between actuator and relay.
  2. If no open is found, replace the unlock relay.

Is the repair complete?

--

System OK

--

8

Replace the inoperative actuator. Refer to Front Side Door Lock Actuator Replacement .

Is the repair complete?

--

System OK

--

9

  1. Locate and repair the open in CKT 295 (GRY) or CKT 255 (GRY/BLK) between the actuator and the relay.
  2. If no open is found, replace the lock relay.

Is the repair complete?

--

System OK

--

10

  1. Locate and repair the open in CKT 694 (TAN) for the left door or CKT 254 (TAN/BLK) wire for the right door between the actuator and the relay.
  2. If no open is found, replace the unlock relay for right door or driver door unlock relay for the left door.

Is the repair complete?

--

System OK

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